I've sometimes wondered about this as well. We can all understand how saws work; but can you actually make one from scratch? How about a rope? Do you know where to find the right kind of fibre, how to correctly process it, and then make it in to a functional rope? Do you have the know-how to functionally domesticate wild animals and cultivate crops?
I'd consider myself a pretty handy guy, but if I were whisked away to 70k years ago this very minute then I'd probably struggle with a lot of that, even though I roughly know how to do it. And that is ignore the obvious communication barriers, that you also need to spend time on basic survival, and things like that. A lot of these crafts developed over generations partly because while the concepts aren't all that complex, the actual doing of it in a way that's effective is a lot harder.
I certainly think it'll take a lot more than "days or weeks".
The problem was not to make things, ancients were able to produce few very advanced tools, mechanisms, and technologies, but to save them and pass knowledge of making them to future generations.
To make a dent, you will need a tool for mass spreading of knowledge en masse: a church, a library, a copier, or a book making machine.
I'd consider myself a pretty handy guy, but if I were whisked away to 70k years ago this very minute then I'd probably struggle with a lot of that, even though I roughly know how to do it. And that is ignore the obvious communication barriers, that you also need to spend time on basic survival, and things like that. A lot of these crafts developed over generations partly because while the concepts aren't all that complex, the actual doing of it in a way that's effective is a lot harder.
I certainly think it'll take a lot more than "days or weeks".